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Q: How do I block or bypass hot water to the cabin coils on 1993 Mercedes-Benz 500SEL

air condition works great, when the hot car is parked shortly, I get heat in 2 side air registers mixing with the cold air. when it happens I shut down the 2 registers and divert the cold air to the center registers by switching on the extra air blower.
The back seat air condition duct delivers cold air all the time, no problem there. I live in Florida, do not have to heat the car it is hot enough, that is the reason I want to bypass all the hot water that goes to the cabin. HELP
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Hi Jack,

*** Only work on the system when the engine is completely stone cold and has sat overnight ***

*** Extremely HOT otherwise *** Be careful ***

The Easiest way would be to disconnect the Hoses going in and out of the heater core at the firewall.

Install a piece of non corrosive metal pipe and clamp them together so they have proper flow.

Good Luck and Be Safe!


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